#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, const char **argv) {
  // int ret = execl("/bin/ls","ls","-l",NULL);
  // int ret = execlp("ls","ls","-l",NULL);

  char *buf[] = {"ls", "-l", NULL};
  int ret = execv("/bin/ls", buf);

  // char *buf[] = {"ls", "-l", NULL};
  // int ret = execvp("ls", buf);
  if (ret < 0) {
    perror("execl is fail");
    exit(-1);
  }

  return 0;
}
